You are misunderstanding how the Scientific Method work. It would include number of steps or stages, and always start with the initial observations of phenomena that can be either DIRECTLY observed or INDIRECTLY observed (evidence), BEFORE the
initial assumptions (this “initial assumption” is known as
FORMULATION OF THE QUESTION in Scientific Method) are ever made.
The initial observations of the phenomena plus initial assumptions always begin in Scientific Method, before starting the explanations to a model - known as
FORMULATION OF HYPOTHESIS.
But one thing should know that observation can occur at any time, including between stages of Scientific Method or during the stage of Formulation of Hypothesis.
So not only you can have initial observations before initial assumptions (Formulation of Questions), you can have -
- “follow-up observations” between Formulation of Questions and Formulation of Hypothesis,
- and more “follow-up observations” during scientist(s) writing up the hypothesis.
Once you have completed the hypothesis, then the next stages in scientific method is the testing stage, meaning more observations, and analysis of observations and evidence. You can and would do these stages -
TEST then
ANALYSIS - as many times as necessary, to acquire as many test results and evidence as possible, before reaching the
CONCLUSION.
Scientists who start the investigation of phenomena are not restricted initial observations before the first set of assumptions and testing stage of scientific method. Observations or gathering of evidence can occur at anytime, anywhere.
What I mean by “anywhere” is that observations can happen in the field, hence “fieldwork”, or it can happen in controlled environment like laboratory for experiments.
Ideally, field observations and test results in lab experiments are both desirable to maximize the numbers of observations.
Every evidence will yield data, like measurements, quantities and any other properties.
But even when the whole scientific method is completed and the hypothesis along with evidence and data submitted for PEER REVIEW...even after hypothesis is accepted and the hypothesis has been elevated to
Scientific Theory status, a good solid model (theory) will include more observations post-scientific-method in the years and decades that follow.
For example. When Natural Selection was first published in 1859, (On Origin Of Species), particularly with human evolution, paleontologists did stop looking for more evidence after they first identified the Homo erectus in Java and then another one in China.
Finding more evidence and identifying other species of the genus Homo continued throughout the 20th century to this very day.
Science don’t stop looking for more evidence simply because of being a successful hypothesis has been accepted as a scientific theory.
Even when CMBR was discovered in 1964, astronomers, astrophysicists and cosmologists didn’t stop with this discovery alone. They continued trying to get better images of CMBR in the decades that followed, including launching COBE, WMAP and Planck spacecraft, each times getting better resolution, which yielded more information than the original discovery.
Science don’t stop searching for new evidence that could increase our knowledge in specific fields.